Cardiovascular Outcome Trials in Type 2 Diabetes: What Do They Mean for Clinical Practice?

Buyang huanwu decoction inhibits diabetes-accelerated atherosclerosis via reduction of AMPK-Drp1-mitochondrial fission axis

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese drugs, including Buyang Huanwu decoction (BYHWD), have been used in traditional practice to manage cardiovascular and cerebrovascular diseases. However, the effect and mechanisms by which this decoction alleviates diabetes-accelerated atherosclerosis are unknown and require exploration.

AIM OF THE STUDY

This study aims to investigate the pharmacological effects of BYHWD on preventing diabetes-accelerated atherosclerosis, and elucidate its underlying mechanism.

MATERIALS AND METHODS

Streptozotocin (STZ)-induced diabetic ApoE^-/- mice were treated with BYHWD. Atherosclerotic aortic lesions, endothelial function, mitochondrial morphology, and mitochondrial dynamics-related proteins were evaluated in isolated aortas. High glucose-exposed human umbilical endothelial cells (HUVECs) were treated with BYHWD and its components. AMPK siRNA transfection, Drp1 molecular docking, Drp1 enzyme activity measurement, and so on were used to explore and verify the mechanism.

RESULT

BYHWD treatment inhibited the worsening of diabetes-accelerated atherosclerosis by lessening atherosclerotic lesions in diabetic ApoE^-/- mice, by impeding endothelial dysfunction under diabetic conditions, and by inhibiting mitochondrial fragmentation by lowering protein expression levels of Drp1 and mitochondrial fission-1 protein (Fis1) in diabetic aortic endothelium. In high glucose-exposed HUVECs, BYHWD treatment also downgraded reactive oxygen species, promoted nitric oxide levels, and abated mitochondrial fission by reducing protein expression levels of Drp1 and fis1, but not mitofusin-1 and optic atrophy-1. Interestingly, we found that BYHWD's protective effect against mitochondrial fission is mediated by AMPK activation-dependent reduction of Drp1 levels. The main serum chemical components of BYHWD, ferulic acid, and calycosin-7-glucoside, can reduce the expression of Drp1 by regulating AMPK, and can inhibit the activity of GTPase of Drp1.

CONCLUSION

The above findings support the conclusion that BYHWD suppresses diabetes-accelerated atherosclerosis by reducing mitochondrial fission through modulation of the AMPK/Drp1 pathway.

A Critical View over the Newest Antidiabetic Molecules in Light of Efficacy-A Systematic Review and Meta-Analysis

The increase in life expectancy without a decrease in the years lived without disability leads to the rise of the population aged over 65 years prone to polypharmacy. The novel antidiabetic drugs can improve this global therapeutic and health problem in patients with diabetes mellitus (DM). We aimed to establish the efficacy (A1c hemoglobin reduction) and safety of the newest antidiabetic drugs (considered so due to their novelty in medical practice use), specifically DPP-4i, SGLT-2i, GLP-1 Ra, and tirzepatide. The present meta-analysis followed the protocol registered at Prospero with the CRD42022330442 registration number. The reduction in HbA1c in the DPP4-i class for tenegliptin was 95% CI -0.54 [-1.1, 0.01], p = 0.06; in the SGLT2-iclass for ipragliflozin 95% CI -0.2 [-0.87, 0.47], p = 0.55; and for tofogliflozin 95% CI 3.13 [-12.02, 18.28], p = 0.69, while for tirzepatide it was 0.15, 95% CI [-0.50, 0.80] (p = 0.65). The guidelines for treatment in type 2 DM are provided from cardiovascular outcome trials that report mainly major adverse cardiovascular events and data about efficacy. The newest antidiabetic non-insulinic drugs are reported to be efficient in lowering HbA1c, but this effect depends between classes, molecules, or patients' age. The newest antidiabetic drugs are proven to be efficient molecules in terms of HbA1c decrease, weight reduction, and safety, but more studies are needed in order to characterize exactly their efficacy and safety profiles.

Fragility of cardiovascular outcome trials (CVOTs) examining nutrition interventions among patients with diabetes mellitus: a systematic review of randomized controlled trials

PURPOSE

There is controversy regarding the optimal statistical method to interpret how robust is a statistically significant result. The fragility index (FI) and the reverse fragility index (RFI) are quantitative measures that can facilitate the appraisal of a clinical trial's robustness. This study was performed to evaluate the FI and RFI of randomized controlled trials (RCTs) examining nutritional interventions in patients with diabetes mellitus, focusing on cardiovascular outcomes.

METHODS

A systematic search was conducted and relevant RCTs were identified in three databases. RCTs examining nutritional interventions (supplements or dietary patterns) in patients with DM with dichotomous primary endpoints involving cardiovascular outcomes were eligible. Data were extracted to compose 2 × 2 event tables and the FI and RFI were calculated for each comparison, using Fisher's exact test. Risk of bias (RoB) of the included RCTs was assessed with the Cochrane RoB 2.0 tool.

RESULTS

A total of 14,315 records were screened and 10 RCTs were included in the analyses. The median FI of the paired comparisons was 3 (IQR: 2-4) and the median RFI was 8 (IQR: 4.5-17). RoB and heterogeneity were low.

CONCLUSIONS

RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus appear to be statistically fragile. Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness.

HIGHLIGHTS

• In the evidence-healthcare era, assessing how robust statistically significant results are remains a matter of controversy. • Recently, the fragility index (FI) and reverse fragility index (RFI) were proposed to assess the robustness of randomized controlled trials (RCTs) with 2 × 2 comparisons. • When applying the FI and RFI, RCTs examining nutritional interventions and cardiovascular outcomes among patients with diabetes mellitus (DM) appear to be statistically fragile. • Τhe FI and the RFI can be reported and interpreted as an additional perspective of a trial's robustness. • RCTs implementing nutrition interventions among patients with DM can improve their methodology.

Metabolic Associated Fatty Liver Disease (MAFLD) Increases the Risk of Systemic Complications and Mortality. A Meta-Analysis and Systematic Review of 12,620,736 Individuals

INTRODUCTION

The recent introduction of the definition "metabolic associated fatty liver disease" (MAFLD) sought to reclassify non-alcoholic fatty liver disease (NAFLD). MAFLD is thought to improve the encapsulation of metabolic dysregulation. However, recent evidence has found significant differences between MAFLD and NAFLD and prevailing knowledge has largely arisen from studies in NAFLD. Hence, we conducted a meta-analysis and systematic review on the outcomes associated with MAFLD.

METHODS

Medline and Embase database were searched for articles relating to outcomes in MAFLD. Analysis was conducted in random effects with hazard ratios to account for longitudinal risk assessment of mortality and systemic complications.

RESULTS

A total of 554 articles were identified and a final total of 17 articles were included. MAFLD resulted in an increase of overall mortality (HR 1.24, CI: 1.13 - 1.34), cancer related mortality (HR: 1.27, CI: 1.01 - 1.54) and CVD mortality (HR: 1.28, 1.03 - 1.53, p=0.04) compared to non MAFLD. MAFLD also increases the risk of cardiovascular events (HR: 1.49, CI: 1.34 - 1.64, p<0.01), stroke (HR: 1.55, CI: 1.37 - 1.73, p<0.01) and chronic kidney disease (HR: 1.53, CI: 1.38 - 1.68). The presence of MAFLD was also associated with an increased risk of heart failure, obstructive sleep apnoea and malignancy.

CONCLUSIONS

MAFLD can significantly elevate the risk of systemic diseases and mortality. The care of MAFLD thus requires interdisciplinary collaboration and future clinical trials conducted in MAFLD should aim to reducing the incidence of end organ damage aside from improving liver histology.

Sodium-Glucose Cotransporter 2 Inhibitors and Heart Failure: A Bedside-to-Bench Journey

Type 2 diabetes mellitus (T2DM) and heart failure (HF) are multifactorial diseases sharing common risk factors, such as obesity, hyperinsulinemia, and inflammation, with underlying mechanisms including endothelial dysfunction, inflammation, oxidative stress, and metabolic alterations. Cardiovascular benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors observed in diabetic and non-diabetic patients are also related to their cardiac-specific, SGLT-independent mechanisms, in addition to the metabolic and hemodynamic effects. In search of the possible underlying mechanisms, a research campaign has been launched proposing varied mechanisms of action that include intracellular ion homeostasis, autophagy, cell death, and inflammatory processes. Moreover, the research focus was widened toward cellular targets other than cardiomyocytes. At the moment, intracellular sodium level reduction is the most explored mechanism of direct cardiac effects of SGLT2 inhibitors that mediate the benefits in heart failure in addition to glucose excretion and diuresis. The restoration of cardiac Na⁺ levels with consequent positive effects on Ca²⁺ handling can directly translate into improved contractility and relaxation of cardiomyocytes and have antiarrhythmic effects. In this review, we summarize clinical trials, studies on human cells, and animal models, that provide a vast array of data in support of repurposing this class of antidiabetic drugs.

Sex-specific impact of diabetes on all-cause mortality among adults with acute myocardial infarction: An updated systematic review and meta-analysis, 1988-2021

BACKGROUND

The prevalence of diabetes and its impact on mortality after acute myocardial infarction (AMI) are well-established. Sex-specific analyses of the impact of diabetes on all-cause mortality after AMI have not been updated and comprehensively investigated.

OBJECTIVE

To conduct a systematic review and meta-analysis that examined sex-specific short-term, mid-term and long-term all-cause mortality associated with diabetes among AMI survivors (diabetes versus non-diabetes patients in men and women separately), using up-to-date data.

METHODS

We systematically searched Embase and MEDLINE for studies that were published from inception to November 14, 2021. Studies were included if (1) they studied post-AMI all-cause-mortality in patients with and without diabetes, (2) sex-specific all-cause mortality at short-term (in-hospital or within 90 days after discharge), mid-term (>90 days and within 5 years), and/or long-term (>5 years) were reported. From eligible studies, we used random effects meta-analyses models to estimate pooled unadjusted and adjusted sex-specific risk ratio (RR) of all-cause mortality at short-, mid-, and long-term follow-up for adults with diabetes compared with those without diabetes.

RESULTS

Of the 3647 unique studies identified, 20 studies met inclusion criteria. In the unadjusted analysis (Total N=673,985; women=34.2%; diabetes patients=19.6%), patients with diabetes were at a higher risk for all-cause mortality at short-term (men: RR, 2.06; women: RR, 1.83); and mid-term follow-up (men: RR, 1.69; women: RR, 1.52) compared with those without diabetes in both men and women. However, when adjusted RRs were used (Total N=7,144,921; women=40.0%; diabetes patients=28.4%), the associations between diabetes and all-cause mortality in both men and women were attenuated, but still significantly elevated for short-term (men: RR, 1.16; 95% CI, 1.12-1.20; women: RR, 1.29; 95% CI, 1.15-1.46), mid-term (men: RR, 1.39; 95% CI, 1.31-1.46; women: RR, 1.38; 95% CI, 1.20-1.58), and long-term mortality (men: RR, 1.58; 95% CI, 1.22-2.05; women: RR, 1.76; 95% CI, 1.25-2.47). In men, all-cause mortality risk associated with diabetes tended to increase with the duration of follow-up (p<0.0001).

CONCLUSIONS

Diabetes has substantial and sustained effects on post-AMI all-cause mortality at short-term, mid-term and long-term follow-up, regardless of sex. Tailoring AMI treatment based on patients' diabetes status, duration of follow-up and sex may help narrow the gap in all-cause mortality between patients with diabetes and those without diabetes.

Cardiovascular Outcomes Trials of Incretin-Based Therapies

The cardiovascular (CV) safety of glucagon-like peptide 1 (GLP-1) receptor agonists has been established in robust cardiovascular outcomes trials (CVOTs) in patients with type 2 diabetes at high CV risk. The GLP-1 receptor agonists liraglutide, dulaglutide, and injectable semaglutide demonstrated a significant CV benefit in these trials and now have indications to reduce the risk of major adverse CV events, including CV death, myocardial infarction, and stroke in adult patients with type 2 diabetes and established cardiovascular disease or high CV risk (dulaglutide). The dipeptidyl peptidase 4 inhibitors have also demonstrated CV safety in dedicated CVOTs but have not been associated with any CV benefit. Guidelines for the treatment of type 2 diabetes have evolved from a glucocentric focus to one that now focuses on reducing overall CV risk by personalizing therapy and using drugs such as GLP-1 receptor agonists with proven CV benefits.

Sodium-Glucose Co-transporter 2 Inhibitors in Heart Failure: Recent Data and Implications for Practice

Heart failure is a shared chronic phase of many cardiac diseases and its prevalence is on the rise globally. Previous large-scale cardiovascular outcomes trials of sodium.glucose co-transporter 2 (SGLT2) inhibitors in patients with type 2 diabetes (T2D) have suggested that these agents may help to prevent primary and secondary hospitalisation due to heart failure and cardiovascular death in these patients. Data from the Study to Evaluate the Effect of Dapagliflozin on the Incidence of Worsening Heart Failure or Cardiovascular Death in Patients With Chronic Heart Failure (DAPA-HF) and Empagliflozin Outcome Trial in Patients With Chronic Heart Failure With Reduced Ejection Fraction (EMPEROR-Reduced) have demonstrated the positive clinical impact of SGLT2 inhibition in patients with heart failure with reduced ejection fraction both with and without T2D. These data have led to the approval of dapagliflozin for the treatment of patients with heart failure with reduced ejection fraction, irrespective of T2D status. This article reviews the latest data reported from the DAPA-HF and EMPEROR-Reduced trials and their clinical implications for the treatment of patients with heart failure.